LuxRender 0.9 Opacity Bug?

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LuxRender 0.9 Opacity Bug?

Hi, I have some issues with opacity of objects in LuxRender 0.9 OpenCL...

Here an example: I did this picture for a friend: http://img862.imageshack.us/img862/6475/bug1x.jpg

To remove the landing gears, I set their materials at 0% opacity, and when exporting with Reality, I set them to NULL. They are no more visible: http://img651.imageshack.us/img651/1543/bug2lp.jpg

...BUT...

...look what happens in the rendering: http://img804.imageshack.us/img804/9272/bug3m.jpg

Never got this problem with version 0.8 of LuxRender:(

MCMXC

Posts: 52
Joined: Fri Nov 04, 2011 12:32 pm
Location: Italy

Re: LuxRender 0.9 Opacity Bug?

What's your current light bounce depth? It should be fairly high to account for all possible transitions through null materials.
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SATtva

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Re: LuxRender 0.9 Opacity Bug?

It would be easier to just move the gears to another layer or prevent that they get exported (don't know if these possibilitys exist in DAZstudio, in Blender they do).

Though this scene could uncover a bug with the null material unless you made a mistake, like forgot to assign a null material to the whole landing gears construction.

B.Y.O.B.

Posts: 1877
Joined: Wed Nov 10, 2010 4:10 pm
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Re: LuxRender 0.9 Opacity Bug?

SATtva wrote:What's your current light bounce depth? It should be fairly high to account for all possible transitions through null materials.

I'm using a HDRI light, this: http://www.daz3d.com/i/shop/itemdetails/?item=12073

B.Y.O.B. wrote:Though this scene could uncover a bug with the null material unless you made a mistake, like forgot to assign a null material to the whole landing gears construction.

I checked: all the materials of the landing gears objects are set to NULL.

MCMXC

Posts: 52
Joined: Fri Nov 04, 2011 12:32 pm
Location: Italy

Re: LuxRender 0.9 Opacity Bug?

MCMXC wrote:
SATtva wrote:What's your current light bounce depth? It should be fairly high to account for all possible transitions through null materials.

I'm using a HDRI light, this: http://www.daz3d.com/i/shop/itemdetails/?item=12073

I think SATtva meant the Depht-setting in your integrator settings.

B.Y.O.B.

Posts: 1877
Joined: Wed Nov 10, 2010 4:10 pm
Location: Germany

Re: LuxRender 0.9 Opacity Bug?

Hi,

The ray passing through a null material counts as 1 bounce so given the complexity of a landing gear, it is most probable that you are reaching the maximum bouncing depth (thus the black splotches). You should raise the bounce limit.

Jeanphi
jeanphi

Posts: 6569
Joined: Mon Jan 14, 2008 7:21 am

Re: LuxRender 0.9 Opacity Bug?

Thanks, I have to check if I can find this parameter!

MCMXC

Posts: 52
Joined: Fri Nov 04, 2011 12:32 pm
Location: Italy

Re: LuxRender 0.9 Opacity Bug?

...ehmmm... please, can someone tell me where I can find this parameter?^____^;;;;

MCMXC

Posts: 52
Joined: Fri Nov 04, 2011 12:32 pm
Location: Italy

Re: LuxRender 0.9 Opacity Bug?

I must admit I have not used Reality, so I don't know where exactly it's "hiding" this parameter.

However you could manually modify the .lxs file. Open it in notepad or a similar text editor, and find a section which looks like this
Code: Select all
SurfaceIntegrator "bidirectional"   "integer eyedepth" [16] "integer lightdepth" [16]

You may find more parameters than the two above, however those two are the ones to change. Change 16 to say 50 each to begin with. Save and open in LuxRender.
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Lord Crc

Posts: 4446
Joined: Sat Nov 17, 2007 2:10 pm

Re: LuxRender 0.9 Opacity Bug?

It's working, thanks!:)

...but... what if I want to use the ExPhotonMap? Are there any parameters like them, please?

MCMXC

Posts: 52
Joined: Fri Nov 04, 2011 12:32 pm
Location: Italy

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